1. Field of the Invention
The present invention relates to improvements in a battery-operated radio pager, and more specifically to a method and arrangement which enables the need for battery replacement to be indicated in a manner which obviates wastefull overly early replacement.
2. Description of the Prior Art
A radio pager which is equipped with a display function has proven very popular in that a large amount of data can be acquired at one calling as compared with an older style pager which alerts a person to call a single predetermined phone number merely by means of sound and/or flashing light.
In order to prevent the battery-operated pager from being rendered inoperative due to loss of battery voltage, it is a common practice to provide a battery voltage detector and alarm generating circuitry operatively coupled thereto.
Currently, it is common to change the battery of the pager as soon as the voltage produced by the same drops to a predetermined level irrespective of the fact that the battery can still continue to operate the pager for some time. In other words, the predetermined level is set so as to be on the safe side and such that the pager will still continue to operate on the current battery. This avoids the problem that under some circumstances it may not be possible to obtain a new battery quickly enough following the low voltage alert.
That is to say, it is practically impossible for a subscriber to predict the exact time the battery currently in use will fail and become useless due to a further voltage drop. It is therefore a usual practice for a subscriber to replace the old battery with a new one as soon as practical after the battery power drop is detected by the detector.
However, in view of very large number of pager subscribers currently in use around the world, this overly early battery replacement amounts to a vast waste of resources and energy and is contrary to the current trend of protecting global ecology.